when you are in a photography darkroom and become hyper and giddy for no apparent reason and start to dance and sing
Girl 1: "Oh god, Suzie's got hilary-itis again! She's going crazy in there!"
Girl 2: "I wonder what it is about darkrooms that makes people get so hyper?"
Girl 2: "I wonder what it is about darkrooms that makes people get so hyper?"
by smilehme May 16, 2007
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